PERMIT APPLICATION GUIDE FOR FACILITIES
WITH COATING/PAINTING OPERATIONS
Applicants overwhelmed by permit application details for facilities with coating/painting
operations may assess the emissions by review of this guide and avoid common mistakes.
The guide should simplify the task of completing permit applications for facilities with
this type of operation.
DATA YOU WILL NEED TO COMPILE INITIALLY:
a. maximum anticipated hourly and annual usage of each coating material
b. building dimensions: length, width, height (emissions released within a
building are not considered controlled but may have modeling significance)
c. heat input capacity of each large gas heater or oven used in the process (note:
this does not include comfort space heaters)
d. composition of each coating product, usually from Material Safety Data
Sheets
e. stack data: height, diameter, temperature, and flowrate (height is height above
ground level; diameter is diameter at discharge; temperature is an average
temperature; such as 70o for non-heated processes; and flowrate is normally
actual cubic feet per minute. Flowrates are discussed in a later section.)
f. maximum anticipated welding electrode usage (if arc welding conducted)
g. sandblasting: hourly and annual abrasive usage; abrasive type
PROVIDE COMPLETE INFORMATION FOR THE FACILITY
Another common mistake is for an applicant to send in an incomplete application, a few
Material Safety Data Sheets, and little else. Failing to properly identify and calculate
emissions is a guarantee of slow processing and frequent Enforcement referrals. Poorly
prepared applications with incomplete or insufficient information will limit operators to
only those volumes of products shown in their submissions.
DESCRIBE THE PROCESS AT YOUR FACILITY
Process description begins with a discussion of the equipment and a flow diagram of the
processes at the facility. Describe the equipment used and draw a process flow diagram
of process points. Process points are known pollution emitting operations that utilize
various methods (spray, roll, dip by hand or machine) to apply materials to surfaces.
Provide rated equipment capacities and maximum process rates at emissions points and
identify whether continuous or batch operations. Provide hours of equipment operation
each year. Include the discharge parameters in the process description (stack height,
diameter, temperature, and exhaust flow rates). Flow rate determinations seem to
challenge applicants the most. A proper process description explains coating/painting
activities just enough to identify air pollution emitting operations and will be less detailed
as would be provided to design engineers, financial planners, etc.
Permit Application Guide
Coating/Painting Operations
1
Revised 12/28/2011
CALCULATE EMISSIONS AT THE FACILITY
In permit language, facility status classification is based upon potential emission rates.
Commonly, applicants mistake or confuse potential and actual emissions, but the two are
related. The potential to emit (PTE, potential emissions) means the maximum potential
of a facility to emit criteria pollutants or hazardous air pollutants (HAP). Potential is
based on equipment capacities but may be influenced by process bottlenecks such as
batch operation or other documented mechanical limits. Actual emissions are based on
control devices or accepted hourly limitations which reduce the potential emissions into
the atmosphere. That’s good because it’s the air we breathe.
Potential Emissions Calculations
Permits reflect both short term (hourly) and long term (annual). Maximum hourly
emissions are based on the maximum hourly performance or production multiplied by a
known related emission factor. Identifiable process bottlenecks which limit production or
equipment operation and affect annual emissions will become part of a permit.
Actual Emissions Calculations
Actual emissions are derived from the facility’s reduced PTE (potential emissions).
Factoring control devices, accepted hourly limits, and accepted production limits results
in actual emissions calculated for pollutants such as particulate matter (PM). Control
devices and equipment have efficiencies expressed as a percentage of pollutant reduced.
To avoid an unduly restrictive permit for the facility if only past rates are known, a
reasonable safety factor should be applied to possibly account for increasing or
fluctuating future business and production.
Example 1:
Emissions of criteria pollutants (such as VOC) and HAP identified at each
process point are individually calculated (hourly and annually). To
calculate the hourly rate, multiply the known emission factor for each
pollutant by the production rate or capacity of the process point. To
calculate the annual rate, multiply the short term emission rates by the
maximum annual operation hours of each process point. VOC emissions
are calculated for each process point. The VOC emitted at all the process
points are then summed facility-wide.
Example 2:
A painting operation may be able to spray 1.5 gallons per hour of paint;
with 8,760 hours in the year, maximum usage would be 13,140 gallons.
However, facilities often accept a lower usage limit (for example, 5,000
gallons) to stay below an emission thresholds at which some regulatory
requirements become applicable. Since those requirements may include
Maximum Achievable Control Technology, it is wise to back-calculate the
operational levels which would trigger additional procedures and capital
expenditures. A facility which has never approached that limit would not
feel restricted by it.
Permit Application Guide
Coating/Painting Operations
2
Revised 12/28/2011
GENERAL INFORMATION
FORMS: Log onto www.deq.state.ok.us and select “Air Quality”, then “Forms” and next
“Air Forms” to obtain the Minor Source Application forms.
FEES: Fees depend on the facility classification type determined from potential emission
rates. Therefore it is essential to determine potential emission rates in order to properly
calculate and pay the correct fees.
EMISSION FACTORS: log onto www.epa.gov/ttn/ and go to “CHIEF”, emission factor site
“AP-42 5th Edition by Section”. We advise applicants read the index or section headings
to AP-42 first to find which operations have readily-available emissions factors that can
be used for their facility.
STACK FLOWS: a few suggestions which may help…
- OSHA requires paint booth face velocity to be at least 100 feet per minute.
For example, a paint booth with a 6’ × 8’ opening should have a discharge rate
of at least 4,800 cubic feet per minute.
- Fire codes require 5 to 6 air exchanges per hour for buildings handling
flammable materials. A building that is 40 feet wide, 25 feet tall, and 100 feet
long has a volume of 100,000 cubic feet. If this building has 8 roof fans, each
fan should discharge 1,250 cubic feet per minute (6 exchanges × 100,000
cubic feet divided by eight fans divided by 60 minutes per hour).
- For natural gas combustion: expect 13.2 standard cubic feet exhausts per cubic
foot of natural gas fuel, then convert volumes to actual; expect stack
temperatures in the range of 400-600oF.
GENERIC SPECIFICATIONS: The best way to gain flexibility in permitting is to
establish a “supercoating” or generic set of specifications for paints, primers, inks,
lacquers, etc. A material safety data sheet (MSDS) for each product discloses physical
properties (e.g. – density, composition or weight percentages of components). You may
compare them to determine the generic specification. The limit may be set by any
product among all others with the greatest amount of any single component (pounds per
gallon). This is then used to set the maximum levels of emission (e.g. – solids, VOCs)
and multiplied by the total usage volume of all the products used. In some cases, you
could have multiple supercoatings, i.e., one for paints, one for primers, etc.
Spray paints from aerosol cans should be in a separate supercoating where applicable.
Permit Application Guide
Coating/Painting Operations
3
Revised 12/28/2011
REGULATORY THRESHOLDS TO OBSERVE
Regulatory requirements may be triggered if a facility reaches certain emissions levels or
is in certain areas.
- Paint operations: 100 lb/day volatile organic compounds emitted;
- Tulsa County: 10 TPY (OAC 252:100-39-46(h))(Note: acetone does not count in that
total);
- Hazardous Air Pollutant (HAP) thresholds:
- 10 TPY of any one HAP
- 25 TPY total HAPs
- 100 TPY any criteria pollutant (including volatile organic compounds or paint solvents)
If you exceed any of these thresholds, there are requirements for additional analyses and
sometimes additional air pollution controls. There is a common misconception that
someone cannot exceed these levels; that is not correct. There are, however,
consequences for exceeding these thresholds that you may or may not find acceptable,
depending on the circumstances.
SAMPLE CALCULATIONS
The procedure begins with an MSDS. List out the product density and approximate the
hourly and annual usage. Multiply the density times hourly/annual usage times the
weight percent for each component. Coating products are typically reported as percentages
by weight, although occasionally volume percentages are reported. Our calculations depend
on weight.
Sometimes, you may assume 50% transfer efficiency (meaning half of all solids stay on
your product). Particulate emissions are be further reduced by the control efficiency of
any filters controlling particle emissions in the spray area. Transfer efficiency is
principally a function of the geometry of the pieces being sprayed, so using 50% is
discouraged if more accurate information is available.
For dip coating, roll coating, or similar operations (other than spraying), emissions of
solid components will be minimal and can be left off.
Suggestion: it has been our experience that these are easier to keep organized if the
components are in alphabetical order.
The following table demonstrates this method for a typical coating product. Note that
each product has to be analyzed in an “as applied” state; that is, if the product has two or
three constituents that must be mixed before application, or if the product is thinned by
addition of a solvent before application, the characteristics of the mixed or thinned
product must be used in the analysis.
Permit Application Guide
Coating/Painting Operations
4
Revised 12/28/2011
Density Hourly Annual
Chemical
Weight Emissions
ppg
Usage
Usage
Constituent
Percent
lb/hr
Gallons Gallons
Acme Coating 10.96
1.5
5000 Total VOC
42%
6.91
XYZ
1,2,4-trimethyl benzene
10%
1.64
aluminum
10%
0.08
aromatic hydrocarbons
20%
3.29
butyl acetate
35%
5.75
ethyl benzene *
5%
0.82
methyl ethyl ketone
1%
0.16
propylene glycol methyl ether
10%
1.64
acetate
Xylene *
10%
1.64
Product
Emissions
TPY
11.51
2.74
0.14
5.48
9.59
1.37
0.27
2.74
* Hazardous Air Pollutant (HAP).
Note that aluminum has been reduced by 50% to account for retention on the product and
a further 90% to account for filter control efficiency. Although the components of the
coating product that one might normally consider to be VOC add to 91%, VOC is
established as only 42%. This is because each component is typically listed with a
content range up to a maximum percentage. For conservative analysis of an individual
component, we always assume the highest content or percent in its range.
DEVELOPING "SUPERCOATINGS" FOR PERMITS
Again, "supercoating" is a set of generic specifications regarding the composition of paints,
inks, lacquers, varnishes, and other surface coating materials. Specifying a supercoating in a
permit provides the maximum flexibility for an operator while minimizing the potential for
having to modify permits. The procedure is designed to conservatively derive a worst-case
set of conditions. Logically, if the worst-case conditions are in compliance with the
applicable standards, then all other conditions will be in compliance, also.
Any given material may have various components that are subject to a federal NSPS or
NESHAP regulation and must be broken down by relative percentages. Once isolated, each
criteria pollutant and each HAP can be properly calculated and a proper determination
made. Permit applications should include a stack of material safety data sheets that state the
product density and proportion (or proportion range) of each hazardous component.
Frequently, products will be listed as "trade secret." Occasionally, the percentage of a single
solvent will exceed the percentage stated to be volatile.
There are 4 steps to develop a supercoating.
1. Divide the MSDSs into categories: topcoats, primers, solvents, etc. Solvents include
those used in surface preparation or in equipment clean-up. If a specific solvent or amount
of solvent is dedicated to mixing with a particular coating product, its quantity may be
grouped with that product to accurately reflect as-applied values, but account for it once.
Permit Application Guide
Coating/Painting Operations
5
Revised 12/28/2011
2.74
2. For each category, calculate the composition of each component on a pounds per gallon
(ppg) basis. When a range is specified, always use the high end of the range.
3. Prepare a table of components and ppg compositions. It is helpful to do them in
alphabetical order.
4. Pick the highest ppg number from each coating.
Doing this procedure, the sum of components will exceed 100%, as noted in the above
discussion of the single product analysis.
NOTE: the abbreviations "MEK" and "MIBK" mean methyl ethyl ketone and methyl
isobutyl ketone, respectively. MEK has been de-listed by the EPA and is no longer
considered a HAP.
Essentially all VOCs in the total of paints and primers applied are emitted. Solids would be
handled almost identically except that both a transfer (retention) efficiency and control
efficiency must be factored in. As discussed earlier, the amount of solids transferred to or
retained on the product is a function of the product’s geometry, and must be estimated for
each specific situation. Commonly, paint booths have filters in the range of 95-99%
efficiency for PM emissions control, but your filter manufacturer’s data should list accurate
information about rated efficiencies for each type of filter medium option.
EXAMPLE SUPERCOATING: A widget factory uses four basic paints: red, blue, black,
and yellow. Specifications for each paint are listed below.
Red
8 ppg
47% total VOC
5-10% MEK
5-15% xylene
10-15% MIBK
10% toluene
Blue
9 ppg
52% total VOC
20% MEK
15% toluene
30% MIBK
Black
10 ppg
30% total VOC
15% acetone
15% xylene
5% butyl cellosolve
Yellow
12 ppg
40% total VOC
12% MEK
18% MIBK
5-10% toluene
5-10% xylene
FIRST: Make a table, preferably in alphabetical order, showing lb/gal concentrations of all
components.
Pollutant
Red
Blue
Black
Yellow
Total VOC
Acetone
Butyl cellosolve
MIBK
Toluene
Xylene
3.76
--1.20
0.80
1.20
4.68
--2.70
1.35
--
3.00
1.50
0.50
--1.5
4.80
--2.16
1.20
1.20
Permit Application Guide
Coating/Painting Operations
6
Highest After
Rounding
Revised 12/28/2011
Next, compare products and select the highest concentration of each pollutant (shown in
bold). Enter that amount into the column marked “highest.”
Pollutant
Total VOC
Acetone
Butyl cellosolve
MEK
MIBK
Toluene
Xylene
Red
3.76
--1.80
1.20
0.80
1.20
Blue
4.68
---2.70
1.35
--
Black
3.00
1.50
0.50
---1.50
Yellow
4.80
---2.16
1.20
1.20
Highest
4.80
***
0.50
1.80
2.70
1.35
1.50
Acetone is excluded from the definition of VOC and is not a toxic HAP nor is MEK.
Therefore, don’t include them as a “supercoating” component.
Amounts listed in column “highest” may now be rounded up slightly to allow some
flexibility, but only if they do not cause the facility to exceed any of the thresholds discussed
earlier. The generic "supercoating" will have the following specifications. Any coating that
meets these specifications will be in compliance with the permit.
Pollutant
Concentration
lb/gal
5.0
0.6
3.0
1.5
1.6
Total VOC
Butyl cellosolve
MIBK
Toluene
Xylene
Suppose now that maximum paint usage is 3 GPH and 10,000 GPY
A simplified calculation of emissions rates follows.
Pollutant
Total VOC
Butyl cellosolve
MIBK
Toluene
Xylene
Concentrations
lb/gal
Hourly usage
gallons
Annual usage
gallons
5.0
0.6
3.0
1.5
1.6
3.0
10,000
Permit Application Guide
Coating/Painting Operations
7
Emissions
lb/hr
TPY
15.00
1.80
9.00
4.50
4.80
10.00
3.00
15.00
7.50
8.00
Revised 12/28/2011
Permit conditions are now appropriate limiting the facility to 3 GPH (24-hour average) and
10,000 gal/yr of paints with the following limitations of solvent content. The operator will
be required to keep records of paint usages and MSDSs for each paint used.
One closing thought: you may wonder why components should be stated as ppg instead of
weight percentages. If an initial coating with a density of 12 ppg and 10% by weight xylene
is replaced by a coating with a density of 8 ppg and 12.5% xylene, the first coating has 1.2
ppg xylene while the replacement has 1.0 ppg. Stating limits in terms of 10% by weight
would result in those limits being violated by an emissions reduction.
HELPFUL DATA
The following emission factors are based on EPA’s “Compilation of Air Pollutant
Emission Factors,” better known as “AP-42.” AP-42 is periodically updated, so limits
based on these factors may become out-of-date. It may be to your advantage to include a
safety factor on calculations provided that the resultant emissions do not exceed any level
of significance such as a regulatory limit or a major source threshold.
A. Natural Gas Combustion Emissions Factors
Pollutant
Emission Factor, lb per million cubic feet
NOx
100
CO
84
VOC
5.8
Particulate Matter
7.6
Sulfur Dioxide
0.6
B. Welding Emissions
Pollutant
Emission Factor, lb per thousand pounds electrode used
PM
8.16
Chromium
2.53
Chromium VI
1.88
Cobalt
0.001
Manganese
2.32
Nickel
1.71
Lead
0.162
C. Sandblasting
- Outdoors using sand: 13 lbs per 1,000 lb abrasive used
- enclosed with baghouse: 0.69 lbs per 1,000 lb abrasive
- grit: 24% of sand
- steel shot: 10% of sand
Permit Application Guide
Coating/Painting Operations
8
Revised 12/28/2011
HAZARDOUS AIR POLLUTANTS
acetaldehyde
acetamide
acetonitrile
acetophenone
2-acetylaminofluorine
acrolein
acrylamide
acrylic acid
acrylonitrile
allyl chloride
4-aminobiphenyl
aniline
o-anisidine
asbestos
benzene
benzidine
benzotrichloride
benzyl chloride
biphenyl
bis(2-ethylhexyl) phthalate - DEHP
bis(chloromethyl)ether
bromoform
1,3-butadiene
calcium cyanamide
caprolactum
captan
carbaryl
carbon disulfide
carbon tetrachloride
carbonyl sulfide
catechol
chloramben
chlordane
chlorine
chloroacetic acid
2-chloroacetophenone
chlorobenzene
chlorobenzilate
chloroform
chloromethyl methyl ether
chloroprene
cresols/cresylic acid (mixed isomers)
o-cresol
m-cresol
p-cresol
cumene
2,4-D salts and esters
Permit Application Guide
Coating/Painting Operations
styrene
styrene oxide
2,3,7,8-tetrachlorobenzo-p-dioxin
1,1,2,2-tetrachloroethane
tetrachloroethylene (perchloroethylene)
titanium tetrachloride
toluene
2,4 toluene diamine
dibutyl phthalate
p-dichlorobenzene
3,3-dichlorobenzidine
dichloroethyl ether
1,3-dichloropropene
dichlorvos
diethanolamine
N,N-diethyl aniline
diethyl sulfate
3,3-dimethoxy benzidine
dimethyl aminor azobenzene
3,3-dimethyl benzidine
dimethyl carbamoyl chloride
dimethyl formamide
1,1-dimethyl hydrazine
dimethyl phthalate
dimethyl sulfate
4,6-dinitro-o-cresol and salts
2,4-dinitrophenol
2,4-dinitrotoluene
1,4-dioxane (1,4-diethyleneoxide)
1,2-diohenyl hydrazine
epichlorohydrin
1,2-epoxybutane
ethyl acrylate
ethyl benzene
ethyl carbamate (urethane)
ethyl chloride (chloroethane)
ethylene dibromide (dibromoethane)
ethylene dichloride (1,2 dichloroethane)
ethylene glycol
ethylene imine (aziridine)
ethylene oxide
ethylene thiourea
ethylidine dichloride (1,1-dichloroethane
formaldehyde
heptachlor
hexachlorobenzene
hexachlorobutadiene
9
Revised 12/28/2011
DDE
diazomethane
dibenzofurans
1,2-dibromo-3-chloropropane
maleic anhydride
methanol
methoxychlor
methyl bromide (bromomethane)
methyl chloride (chloromethane)
methyl chloroform (1,1,1-trichloroethane)
methyl ethyl ketone (2-butanone) DELISTED 12/05
methyl hydrazine
methyl iodide (iodomethane)
methyl isobutyl ketone (hexanone)
methyl isocyante
methyl methacrylate
methyl tert-butyl ether
4,4-methylene bis(2-chloroaniline)
methylene chloride (dichloromethane)
methylene diphenyl diisocyanate (MDI)
4,4-methylenedianiline
naphthalene
nitrobenzene
4-nitrobiphenyl
4-nitrophenol
2-nitropropane
N-nitroso-N-methylurea
N-nitrosodimethylaniline
N-nitrosomorpholine
parathion
pentachloronitrobenzene
pentachlorophenol
phenol
p-phenylenediamine
phosgene
phosphine
phosphorus
phthalic anhydride
polychlorinated biphenyls
1,3-propane sultone
beta-propiolactone
propionaldehyde
propoxur (Baygon)
1,2-propylene dichloride
propylene oxide
1,2-propylenimine
quinoline
quinone
hexachlorocyclopentadiene
hexachloroethane
hexamethylene-1,6-diisocyanate
hexamethylphosphoramide
hexane
hydrazine
hydrochloric acid
hydrofluoric acid
hydrogen sulfide
hydroquinone
isophorone
lindane (all isomers)
2,4-toluene diisocyante
o-toluidine
toxaphene
1,2,4 trichlorobenzene
1,1,2-trichloroethane
trichloroethylene
2,4,5-trichlorophenol
2,4,6-trichlorophenol
triethylamine
trifluralin
2,2,4-trimethyl pentane
vinyl acetate
vinyl bromide
vinyl chloride
vinylidine chloride
xylene - mixed isomers
o-xylene
m-xylene
p-xylene
antimony compounds
arsenic compounds
beryllium compounds
cadmium compounds
chromium compounds
cobalt compounds
coke oven emissions
cyanide compounds
glycol ethers
lead compounds
manganese compounds
mercury compounds
fine mineral fibers
nickel compounds
polycyclic organic matter
radionuclides (including radon)
selenium compounds
Visit EPA at http://www.epa.gov/ttn/atw/orig189.html for more information.
Permit Application Guide
Coating/Painting Operations
10
Revised 12/28/2011